Multiple ecological factors influence the dynamics of populations, the structure of communities and the functioning of ecosystems. One mechanism to evaluate the multiple levels that influence the distribution of species among sites is to focus on the relationship between environmental gradients and the traits of species that occupy different sites along gradients. This project would use this approach by testing the predictions of a set of mechanistic models by combining experimental approaches and recently developed statistical methods, the 4th corner technique. It will conduct long-term experiments in mesocosms that manipulate nutrients, light and trophic structure to investigate how ecological, morphological and stoichiometric traits are correlated with these factors. Information will be collected to relate patterns in 4th corner matrices directly to the predictions and assumptions of two major alternative hypotheses for the regulation of aquatic food webs in ponds.
